The Jensen JRV215N radio in our Greyhawk came with the iGo Navigation system. Personally, after a weekend with it, I'd recommend using your phone or something else.
I found the menu system archaic. And three times, on three separate routes it told us to "turn right, then turn around then turn right."
Yep - it wanted us to turn right, then go 25-50 yards, then turn around and get right back on the road we were on.
It's better than nothing.
But not too much better.